Toggle operated pinch valves are known. U.S. Pat. No. 3,016,915, for example, discloses a double-acting toggle-operated pinch valve particularly suited for controlling fluid flow through a pair of resilient tubes.
As pointed out in patent, flexible tubing fabricated from resiliently deformable material is widely used to conduct pressurized fluid. In such cases, it is often desirable to provide means to stop fluid flow through one tube quickly and positively, while at the same time to initiate fluid flow through another tube. The fluid flow through both tubes may be controlled by clamps, which is the usual prior art practice. However, such clamps are often relatively slow operating, and it is difficult accurately to relate the stopping of fluid flow in one tube with the initiation of fluid flow in a second tube when clamps are used.
The valve mechanism of U.S. Pat. No. 3,016,915 avoids the use of clamps, but the mechanism disclosed in the Patent is complicated. Accordingly, one objective of the present invention is to provide a pinch valve which may be toggle operated and which is simple in its construction in that it requires relatively few component parts, and yet which is efficient and reliable in its operation.
Push-button operated pinch valves also are known, one such valve being disclosed, for example, U.S. Pat. No. 4,359,067. However, again, the construction of the pinch valve described in U.S. Pat. No. 4,359,067 is somewhat complex. Accordingly, another objective of the present invention is to provide a pinch valve which may be operated either by a toggle lever or by a push-button, and which is simpler in its construction than the prior art pinch valves, and yet is capable of performing operations beyond the scope of the prior art valves.